The Stay With Me hitmaker made his mark in his native U.K. in 2013 but was still a relative unknown when he was chosen to serve as the musical guest on the long-running comedy sketch show in March (14).
Following his performance, he seemingly became an overnight sensation, which Smith himself was hesitant to believe.
He tells the U.K.'s Daily Mirror, "I always thought if America was going to happen it would be two years, three years or after the second record. But everything happened at the same time - it was really weird.
"The minute I did Saturday Night Live everything exploded. I performed Stay With Me for seven million viewers. It is unheard of because the people they normally have on that show are Rihanna and Pharrell Williams. That made it more scary as they were taking a huge chance on me.
"Afterwards I was so relieved. It was the happiest I had ever been in my entire life. It felt like a groundbreaking moment."
However, Smith's big break was marred when he learned his London apartment, where he had been living for three years, had been broken in to.
Smith reveals, "They took champagne and that was it. I think they were classy burglars. I think they looked at my clothes and my size 12 shoes and thought, no. Now I'm in a nice new place with security gates, so I don't need to worry while I'm away."